Gossen's Second “Law”, named for Hermann Heinrich Gossen (1810–1858), is the assertion that an economic agent will allocate his or her expenditures such that the ratio of the marginal utility of each good or service to its price (the marginal expenditure necessary for its acquisition) is equal to that for every other good or service. Formally, where * is utility * is quantity of the -th good or service * is the price of the -th good or service